... additional stuff to this odd edition https://buyee.jp/item/jdirectitems/...c_browsing_hisotry_list#group=nogroup&photo=1 May be, it`s a selfmade merch cassette from Mazda for professional sellers - there are no code on the small sides, and the long narrow front side is without any declaration, - but case is original TDK. I know another TDK "CAR" - cassette : but this fits more to the other gimmick - tapes.
I've got one or two around here, back in the 80's it was normal to have a tape in the new car that might have "stereo" demonstrations or just info on your new car. I wonder if they've become collectable?